U.S. patent number 7,579,276 [Application Number 11/663,179] was granted by the patent office on 2009-08-25 for substrate processing apparatus and method of manufacturing semiconductor device.
This patent grant is currently assigned to Hitachi Kokusai Electric Inc.. Invention is credited to Sadayoshi Horii, Hideharu Itatani, Atsushi Sano, Hidehiro Yanai.
United States Patent |
7,579,276 |
Itatani , et al. |
August 25, 2009 |
Substrate processing apparatus and method of manufacturing
semiconductor device
Abstract
To prevent particles from generating by reducing a contact-gas
area and improve a purge efficiency by reducing a flow passage
capacity. There is provided a substrate processing apparatus,
comprising a processing chamber 1 for processing a substrate 2; a
substrate carrying port 10 provided on a sidewall of the processing
chamber 1, for carrying-in/carrying-out the substrate 2 to/from the
processing chamber 1; a holder provided so as to be lifted and
lowered in the processing chamber 1, for holding the substrate 2;
supply ports 3 and 4 provided above the holder, for supplying gas
into the processing chamber 1; an exhaust duct 35 provided on the
peripheral part of the holder, for exhausting the gas supplied into
the processing chamber 1; and an exhaust port 5 provided below an
upper surface of the exhaust duct 35 when the substrate is
processed, for exhausting the gas discharged by the exhaust duct 35
outside the processing chamber 1, wherein at least a part of a
member constituting the exhaust duct 35 is provided so as to be
lifted and lowered.
Inventors: |
Itatani; Hideharu (Nanto,
JP), Yanai; Hidehiro (Toyama, JP), Horii;
Sadayoshi (Toyama, JP), Sano; Atsushi (Toyama,
JP) |
Assignee: |
Hitachi Kokusai Electric Inc.
(Tokyo, JP)
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Family
ID: |
36148455 |
Appl.
No.: |
11/663,179 |
Filed: |
October 14, 2005 |
PCT
Filed: |
October 14, 2005 |
PCT No.: |
PCT/JP2005/018982 |
371(c)(1),(2),(4) Date: |
May 03, 2007 |
PCT
Pub. No.: |
WO2006/041169 |
PCT
Pub. Date: |
April 20, 2006 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20070264840 A1 |
Nov 15, 2007 |
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Foreign Application Priority Data
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Oct 15, 2004 [JP] |
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2004-302323 |
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Current U.S.
Class: |
438/681; 438/785;
257/E21.586; 257/E21.477; 118/503 |
Current CPC
Class: |
C23C
16/4412 (20130101) |
Current International
Class: |
H01L
21/44 (20060101) |
Field of
Search: |
;438/681,785,788,680
;118/729,503 ;427/255.28 ;257/E21.477,E21.478,E21.586 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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A 2001-329370 |
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Nov 2001 |
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JP |
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A 2002-270594 |
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Sep 2002 |
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JP |
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A 2003-347298 |
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Dec 2003 |
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JP |
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A 2004-14952 |
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Jan 2004 |
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JP |
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A 2004-158811 |
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Jun 2004 |
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JP |
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Primary Examiner: Everhart; Caridad M
Attorney, Agent or Firm: Oliff & Berridge, PLC
Claims
The invention claimed is:
1. A substrate processing apparatus comprising: a processing
chamber for processing a substrate; a substrate carrying port
provided on a sidewall of said processing chamber, for
carrying-in/carrying-out said substrate to/from said processing
chamber; a holder provided so as to be lifted and lowered in said
processing chamber, for holding said substrate; a supply port
provided above said holder, for supplying gas into said processing
chamber; an exhaust duct provided on the peripheral part of said
holder, for exhausting the gas supplied into said processing
chamber; and an exhaust port provided below an upper surface of
said exhaust duct when the substrate is processed, for exhausting
the gas discharged by said exhaust duct outside said processing
chamber, wherein said exhaust duct is constituted by a plate having
a hollow part that communicates with said processing chamber, and a
part of said plate is placed on said holder so as to cover at least
a part of an upper surface of said holder.
2. The substrate processing apparatus according to claim 1, wherein
said hollow part is provided between the sidewall of said
processing chamber and a sidewall of said holder.
3. The substrate processing apparatus according to claim 1, further
comprising a controller for controlling to supply two kinds or more
of reactive gases alternately for a plurality of times from said
supply port, and interpose a supply of purge gas between alternate
supplies of said two kinds of more of reactive gases.
4. A substrate processing apparatus, comprising: a processing
chamber for processing a substrate; a substrate carrying port
provided on a sidewall of said processing chamber, for
carrying-in/carrying-out said substrate to/from said processing
chamber; a holder provided so as to be lifted and lowered in said
processing chamber, for holding said substrate; a supply port
provided above said holder, for supplying gas into said processing
chamber; an exhaust duct provided on the peripheral part of said
holder, for exhausting the gas supplied into said processing
chamber; and an exhaust port provided below an upper surface of
said exhaust duct when the substrate is processed, for exhausting
the gas discharged by said exhaust duct outside said processing
chamber, wherein said exhaust duct is constituted by a plate having
a hollow part that communicates with said processing chamber, and
said plate is composed of a first plate having a recessed part and
being provided so as to be lifted and lowered and a second plate
covering said recessed part, and they are separately provided.
5. The substrate processing apparatus according to claim 4, wherein
said second plate is held at a substrate processing position.
6. The substrate processing apparatus according to claim 4, further
comprising a controller for controlling to supply two kinds or more
of reactive gases alternately for a plurality of times from said
supply port, and interpose a supply of purge gas between alternate
supplies of said two kinds or more of reactive gases.
7. The substrate processing apparatus according to claim 4, wherein
said second plate has an inside plate and an outside plate, and
said inside plate is placed on said outside plate.
8. The substrate processing apparatus according to claim 7, wherein
only said inside plate is brought into contact with said first
plate, and said outside plate is not brought into contact with said
first plate, in a state of moving said substrate to a substrate
processing position.
9. The substrate processing apparatus according to claim 8, wherein
a discharge port for discharging the gas into said hollow part of
said plate from said processing chamber is formed by a gap formed
between said inside plate and said outside plate in a state of
moving said substrate to said substrate processing position.
10. A method of manufacturing a semiconductor device, comprising:
carrying a substrate into a processing chamber; placing said
substrate carried into said processing chamber on a holder by
lifting said holder; processing said substrate by discharging gas
by an exhaust duct provided on the peripheral part of said holder
while supplying the gas to said substrate placed on said holder,
and exhausting the gas discharged by said exhaust duct, outside
said processing chamber from an exhaust port provided below an
upper surface of said exhaust duct; setting said substrate after
processing possible to be carried out by lowering said holder; and
carrying out said substrate after processing from said processing
chamber, wherein said exhaust duct is constituted by a plate having
a hollow part that communicates with said processing chamber, and a
part of said plate is placed on said holder so as to cover at least
a part of an upper surface of said holder; and wherein in the step
of lifting and lowering said holder, at least a part of said plate
constituting said exhaust duct is lifted and lowered together with
said holder.
11. The method of manufacturing the semiconductor device according
to claim 10, wherein in the step of processing the substrate, two
kinds or more of reactive gases are alternately supplied to said
substrate for a plurality of times, and supply of purge gas is
interposed between the alternate supplies of said two kinds or more
of the reactive gases.
12. A method of manufacturing a semiconductor device, comprising:
carrying a substrate into a processing chamber; placing said
substrate carried into said processing chamber on a holder by
lifting said holder; processing said substrate by discharging gas
by an exhaust duct provided on the peripheral part of said holder
while supplying the gas to said substrate placed on said holder,
and exhausting the gas discharged by said exhaust duct outside said
processing chamber from an exhaust port provided below an upper
surface of said exhaust duct; setting said substrate after
processing possible to be carried out by lowering said holder; and
carrying out said substrate after processing from said processing
chamber, wherein said exhaust duct is constituted by a plate having
a hollow part that communicates with said processing chamber and
said plate is composed of a first plate having a recessed part and
a second plate covering said recessed part, and they are separately
provided; and wherein in the step of lifting and lowering said
holder, said first plate is lifted and lowered together with said
holder.
13. The method of manufacturing the semiconductor device according
to claim 12, wherein in the step of processing the substrate, two
kinds or more of reactive gases are alternately supplied to said
substrate for a plurality of times, and supply of purge gas is
interposed between the alternate supplies of said two kinds or more
of the reactive gases.
Description
TECHNICAL FIELD
The present invention relates to a substrate processing apparatus
for processing a substrate, with the substrate held by a liftably
moving holder, and a method of manufacturing a semiconductor
device.
BACKGROUND ART
In recent years, since a semiconductor becomes finer to meet a
demand for further high quality semiconductor film, a deposition
process of an atomic layer level for alternately supplying two or
more kinds of reactive gases is focused. As a material of such
reactive gases, a reaction of a metal-containing raw material and a
gas containing oxygen or nitrogen is utilized.
The deposition process can be roughly divided in two according to a
reaction type. One of them is an ALD (Atomic Layer Deposition), and
the other of them is a MOCVD (Metal Organic Chemical Vapor
Deposition) in which a cycle-method is applied (for example see
patent documents 1 and 2). The aforementioned methods have a basic
gas supplying method in common, and therefore an explanation is
given by using FIG. 17. FIG. 17(a) is a flowchart, and FIG. 17(b)
is a gas supplying timing diagram. In an example shown in the
figure, a vaporized metal containing raw material is represented by
a raw material A, and the gas containing oxygen or nitrogen is
represented by a raw material B.
In a case of the ALD, in step 1, the raw material A is supplied to
a substrate and adsorbed on the substrate. In step 2, a residual
raw material A is exhausted. In step 3, the raw material B is
supplied to the substrate, and the raw material B is allowed to
react with the raw material A, to perform deposition. In step 4,
the residual raw material B is exhausted. The ALD method is the
method of repeatedly perform cycles more than once, with the
aforementioned four steps set as one cycle. As is shown in the gas
supplying timing of FIG. 17(b), when the raw material A and the raw
material B are alternately supplied, exhaustion by purge gas is
executed.
In the MOCVD, in which the cycle method is applied, in step 1, the
raw material A is supplied to the substrate, which is then
thermally decomposed, to perform deposition. In step 2, the
residual raw material A is exhausted. In step 3, the raw material B
is supplied to the substrate and a film modifying process for a
deposited film is performed. In step 4, the residual raw material B
is exhausted. The MOCVD method, in which the cycle method is
applied, is the method of repeatedly perform cycles more than once,
with the aforementioned four steps set as one cycle. As is shown in
the gas supplying timing of FIG. 17(b), when the raw material A and
the raw material B are alternately supplied, exhaustion by purge
gas is executed.
Generally, the raw material A and the raw material B have extremely
high reactivity in many cases, and when these raw materials are
simultaneously supplied, a foreign matter is generated by
vapor-phase reaction and a deposition of a film with deteriorated
film quality is generated, thus causing a decline in yield ratio.
Therefore, in the aforementioned steps 2 and 4, purge (exhaustion)
by evacuation and inert gas is executed, so that the gaseous
starting material supplied in the aforementioned previous steps 2
and 4 does not remain. Particularly, a residual gas on the upstream
side of the substrate immediately affects a deposition condition of
the substrate, and therefore a sufficient exhaustion is
required.
However, if it takes long time for exhaustion, although the
sufficient exhaustion is enabled, there is a problem that a
throughput in productivity is deteriorated.
Also, in a case of the ALD, there is a possibility that a film is
deposited all over the area where the raw material in a processing
chamber is adsorbed, thus producing particles. Therefore, a
contact-gas area of the gaseous starting material is required to be
made small as much as possible. Simultaneously, in order to shorten
a substitution time of two or more kinds of the starting gases, a
flow passage capacity of the gaseous starting material is also
required to be made small as much as possible.
Also, a single wafer type apparatus for processing substrates sheet
by sheet becomes a main stream as a semiconductor manufacturing
device for executing the aforementioned deposition method. In order
to form a high quality film with high productivity by using the
single wafer type apparatus, gas supply and an exhaustion method
are important, from the viewpoint of the aforementioned particles
and throughput.
Patent document 1: Japanese Patent Laid Open No. 2003-347298
Patent document 2: Japanese Patent Laid Open No. 2004-158811
DISCLOSURE OF THE INVENTION
Problem to be Solved by the Invention
Generally, the single wafer type apparatus is provided with a
holder (susceptor) for holding the substrate and a lifting/lowering
mechanism whereby this holder is liftably moved. A transfer chamber
provided with a transfer robot is connected to a processing chamber
provided with this holder. During carry-in and carry-out of the
substrate, the substrate is carried in the processing chamber from
the transfer chamber by the transfer robot in a lower part of the
processing chamber by lowering the holder thereto, or the substrate
is carried out from the processing chamber to the transfer
chamber.
During processing the substrate, the processing chamber is shut off
from the transfer chamber, and the holder is lifted when the
substrate is processed in an upper part of the processing chamber.
Therefore, a driving part of the holder is provided in the lower
part of the processing chamber, and a carrying port of the
substrate is provided on the sidewall of the processing chamber. A
gate valve for shutting off the processing chamber from the
transfer chamber is provided in this carrying port.
In a conventional single wafer type apparatus, when a processing
gas is supplied during processing the substrate, gas is supplied
not only to the substrate in the upper part of the processing
chamber but also to a space (in the lower part of the processing
chamber) formed on the backside of the holder by lifting of the
holder. Therefore, a film is unavoidably deposited on a bottom part
of the processing chamber and the driving part, the carrying port,
and the gate valve, etc. It is difficult to remove the film by gas
cleaning, thus deposited on the lower part of the processing
chamber and driving part hidden on the backside of the holder, or
the carrying port, and the gate valve, etc. Accordingly, when the
processing gas flows in the lower part of the processing chamber
which is lower than the holder and the film is deposited on the
bottom part of the processing chamber, the carrying port, and the
gate valve, etc, the particles are produced by the peeling of a
deposited film when the driving part is actuated, and the yield
ratio of the semiconductor would be deteriorated. Particularly, in
a case of the ALD, a part of adsorption is not limited to a high
temperature part, but ranges over the whole area, and therefore it
appears that a large problem is thereby caused.
In addition, in a case of the single wafer type apparatus, time
required for each step largely affects the productivity of the
device when the MOCVD, in which the ALD and the cycle method are
applied, is adopted. Therefore, there is a desire to shorten the
time required for each step. In order to respond to this desire, it
is necessary to efficiently supply the processing gas on the
substrate and efficiently purge the residual gas. Accordingly, it
is important to make the contact-gas area in the processing chamber
and the flow passage capacity small as much as possible. However,
in the conventional single wafer type apparatus, when the
processing gas is supplied or the residual gas is purged, the
processing gas and the purge gas unexpectedly flow not only to the
upper part of the processing chamber, but also to the space (lower
part of the processing chamber) formed on the backside of the
holder by the lift of the holder. Therefore, the flow passage
capacity becomes large in the processing chamber, thus making it
difficult to shorten the substitution time of the two or more kinds
of gaseous starting materials. Therefore, it is not easy to improve
the throughput.
In order to solve the above-described problems, an object of the
present invention is to provide the substrate processing apparatus
capable of preventing the particles from being produced and
improving the throughput by reducing the contact-gas area in the
processing chamber and the flow passage capacity, and a method of
manufacturing the semiconductor device.
Means to Solve the Problems
A first invention provides a substrate processing apparatus,
including:
a processing chamber for processing a substrate;
a substrate carrying port provided on a sidewall of the processing
chamber, for carrying-in/carrying-out the substrate to/from the
processing chamber;
a holder provided so as to be lifted and lowered in the processing
chamber, for holding the substrate;
a supply port provided above the holder, for supplying gas into the
processing chamber;
an exhaust duct provided on the peripheral part of the holder, for
exhausting the gas supplied to the processing chamber; and
an exhaust port provided below an upper surface of the exhaust duct
when the substrate is processed, for exhausting the gas discharged
by the exhaust duct outside the processing chamber,
wherein at least a part of a member constituting the exhaust duct
is provided so as to be lifted and lowered.
In the aforementioned structure, when the substrate is carried in
the processing chamber, by lifting the holder, the substrate
carried in the processing chamber is placed on the holder. When the
holder is lifted, at least a part of the member constituting the
exhaust duct is accordingly lifted. The substrate is processed by
exhausting the gas by the exhaust duct provided on the peripheral
part of the holder, while supplying the gas to the substrate placed
on the holder. The gas exhausted by the exhaust duct is exhausted
outside the processing chamber by the exhaust port provided below
the upper surface of the exhaust duct. After processing the
substrate, by lowering the holder, the substrate after processing
is set in a state possible to be carried out. When the holder is
lowered, at least a part of the member constituting the exhaust
duct is accordingly lowered. The substrate after processing is
carried out of the processing chamber.
According to the present invention, by providing the exhaust duct
on the peripheral part of the holder, for exhausting the gas
supplied to the processing chamber, the gas supplied to the upper
part of the processing chamber above the holder is discharged from
the peripheral part of the holder to the exhaust port through the
exhaust duct. Accordingly, turn-around of the gas to the lower part
of the processing chamber below the holder can be prevented. In
addition, at least a part of the member constituting the exhaust
duct is liftably constituted, and when the substrate is processed,
the holder is lifted and a part of the exhaust duct is also lifted
accordingly. Therefore, the contact-gas area and the gas flow
passage capacity can be reduced.
A second invention provides the substrate processing apparatus
according to the first invention, wherein at least a part of the
member constituting the exhaust duct is linked with the holder and
is lifted together with the holder. In a structure that at least a
part of the member constituting the exhaust duct is linked with the
holder and is lifted together with the holder, when the substrate
is processed and the holder is lifted, a part of the exhaust duct
is also lifted together with the holder. Therefore, the contact-gas
area and the gas flow passage capacity can be reduced.
Also, a part of the exhaust duct is linked and lifted with a
movement of the holder, and therefore when the holder is lifted, a
part of the exhaust duct is also lifted accordingly. Therefore, it
is not necessary to lift a part of the exhaust duct separately
independently. In addition, a lifting means for lifting a part of
the exhaust duct is not required.
A third invention provides the substrate processing apparatus
according to the first invention, wherein at least a part of the
member constituting the exhaust duct is placed on the holder, and
is lifted together with the holder.
When at least a part of the member constituting the exhaust duct is
placed on the holder and is lifted together with the holder, a part
of the exhaust duct is also lifted together with the holder in a
state of being placed on the holder when the substrate is processed
and the holder is lifted. Therefore, the contact-gas area and the
gas flow passage capacity can be reduced.
Also, since a part of the exhaust duct is linked and lifted with
the movement of the holder, by lifting the holder, a part of the
exhaust duct is also automatically lifted along with the lift of
the holder. Therefore, a part of the exhaust duct is not required
to be lifted separately and independently. In addition, a lifting
means for lifting a part of the exhaust duct is not required.
A fourth invention provides the substrate processing apparatus
according to the first invention, wherein at least a part of the
member constituting the exhaust duct is disposed at a position not
facing with a substrate carrying port when the substrate is
carried-in/carried-out, and is disposed at a position facing with
at least a part of the carrying port when the substrate is
processed. Here, as the position not facing with the substrate
carrying port, the position lower than the substrate carrying port
is given as an example. Also, as the position facing at least a
part of the substrate carrying port, a position, where at least a
part of the substrate carrying port is shut, can be given as an
example.
In case that the exhaust duct is fixed to a substrate processing
position, when the substrate is carried-in and carried-out, in
order to enable the substrate to be carried in the processing
chamber, it is necessary to dispose the substrate carrying port
below the exhaust duct, so that the exhaust duct and the substrate
carrying port are not overlapped one another. However, the
processing chamber is thereby made higher.
In this point, according to the substrate processing apparatus of
the present invention, a part of the exhaust duct is liftably
moved, and when the substrate is processed, a part of the exhaust
duct is disposed at a position facing with (overlapping on) a part
of the substrate carrying port. Therefore, the processing chamber
can be made lower by an overlapped portion of a part of the exhaust
duct and a part of the substrate carrying port, and a capacity of
an entire body of the processing chamber can be made smaller. Then,
a flow passage to the substrate carrying port is closed by the
overlapped portion, and the contact-gas area and the flow passage
capacity can be reduced.
In addition, when the substrate is carried-in and carried-out, a
part of the liftably moving exhaust duct is disposed at a position
not facing with (overlapping on) the substrate carrying port, and
therefore the substrate is not inhibited from carrying in/out of
the processing chamber from the substrate carrying port.
A fifth invention provides the substrate processing apparatus
according to the first invention, wherein the exhaust duct is
provided on the side of the holder.
Since the exhaust duct is provided on the side of the holder, the
gas supplied to the processing chamber can be exhausted to the
exhaust port from the side of the holder through the exhaust duct.
Therefore, turn-around of the gas to the lower part of the
processing chamber below the holder can be prevented, and the
contact-gas area and the flow passage capacity can be reduced. In
addition, when the exhaust duct is provided on the side of the
holder, the capacity of the upper part of the processing chamber to
which the gas is supplied when the substrate is processed is made
smaller, compared to a case that the exhaust duct is provided below
the holder. Therefore, the flow passage capacity of the gas can be
made smaller, and the contact-gas area can also be made
smaller.
A sixth invention provides the substrate processing apparatus
according to the first invention, wherein the exhaust duct is
provided so as to close a gap between a sidewall of the processing
chamber and a sidewall of the holder.
By providing the exhaust duct so as to close the gap between the
processing chamber sidewall and the holder sidewall, the
turn-around of the gas to the backside of the holder, passing
through the gap between the processing chamber sidewall and the
holder sidewall can be prevented, and the contact-gas area and the
flow passage capacity can be reduced.
A seventh invention provides the substrate processing apparatus
according to the first invention, wherein the exhaust duct is
constituted by a plate having a hollow part that communicates with
the processing chamber, and is placed on the holder so that a part
of the plate covers at least a part of an upper surface of the
holder.
Since the hollow part of the plate is communicated with the
processing chamber, the gas supplied to the processing chamber by
this hollow part can be exhausted. Also, since the substrate
processing chamber is placed on the holder, so that a part of the
plate covers at least a part of the upper surface of the holder,
the gap can be closed, which is formed between the holder and the
plate when the plate is not placed on the holder so as to cover the
upper surface of the holder. Therefore, the turn-around of the gas
to the backside of the holder from between the holder sidewall and
the plate can be prevented, and the contact-gas area and the flow
passage capacity can be reduced.
An eighth invention provides the substrate processing apparatus
according to the seventh invention, wherein the hollow part is
provided between a processing chamber sidewall and a holder
sidewall.
Since the hollow part is provided between the processing chamber
sidewall and the holder sidewall, the gas supplied to the
processing chamber can be exhausted to the exhaust port from
between the processing chamber sidewall and the holder sidewall
through the hollow part, the turn-around of the gas to the lower
part of the processing chamber below the holder can be prevented,
and the contact-gas area and the flow passage capacity can be
reduced. In addition by providing the hollow part between the
processing chamber sidewall and the holder sidewall, the capacity
of the upper part of the processing chamber to which the gas
supplied when the substrate is processed can be made smaller,
compared to a case that the hollow part is provided below the
holder. Therefore, the flow passage capacity of the gas can be made
smaller, and the contact-gas area can also be made smaller.
A ninth invention provides the substrate processing apparatus
according to the first invention, wherein the exhaust duct is
constituted by a plate having a hollow part that communicates with
the processing chamber, and the plate is composed of a first plate
having a recessed part and a second plate covering the recessed
part, and they are separately provided.
Since the plate is composed of the first plate having the recessed
part and the second plate covering the recessed part, and they are
separately provided, the hollow part can be formed when the second
plate covers the recessed part of the first plate when the
substrate is processed. In addition, since the hollow part thus
formed is communicated with the processing chamber, the gas
supplied to the processing chamber can be exhausted by this hollow
part, and the contact-gas area and the flow passage capacity can be
reduced.
A tenth invention provides the substrate processing apparatus
according to the ninth invention, wherein the first plate is
provided so as to be lifted and lowered, and the second plate is
held at a substrate processing position.
Since the first plate is liftably provided, and the second plate is
held at the substrate processing position, when the substrate is
processed, by lifting the first plate to the substrate processing
position, the hollow part can be formed by covering the recessed
part of the first plate by the second plate, and when the substrate
is carried-in and carried-out, by lowering the first plate to a
substrate carry-in/carry-out position, they can be separated.
An eleventh invention provides the substrate processing apparatus
according to the tenth invention, wherein the second plate has an
inside plate and an outside plate, and the inside plate is placed
on the outside plate.
Since the second plate has the inside plate and the outside plate
and the inside plate is placed on the outside plate, only the
inside plate can be moved without moving the outside plate by
lifting and lowering the first plate.
A twelfth invention provides the substrate processing apparatus
according to the eleventh invention, wherein only the inside plate
is brought into contact with the first plate in a state of moving
the substrate to the substrate processing position, and the outside
plate is not brought into contact with the first plate.
Since only the inside plate is brought into contact with the first
plate in a state of moving the substrate to the substrate
processing position and the outside plate is not brought into
contact with the first plate, the inside plate placed on the
outside plate can be lifted by moving the substrate to the
substrate processing position.
A thirteenth invention provides the substrate processing apparatus
according to the twelfth invention, wherein the discharge port for
discharging the gas into a hollow part of the plate from the
processing chamber is formed by the gap between the inside plate
and the outside plate in a state of moving the substrate to the
substrate processing position.
By a simple structure that the substrate is moved to the substrate
processing position, the discharge port for discharging the gas
into the hollow part of the plate from the processing chamber can
be formed by the gap between the inside plate and the outside
plate.
A fourteenth invention provides the substrate processing apparatus
according to the first invention, further having a controller for
controlling to supply two kinds or more of reactive gases
alternately for a plurality of times from the supply port, and
interpose a supply of purge gas between alternate supplies of the
two kinds of more of the reactive gases.
When a cyclic processing is performed such as alternately supplying
two kinds of more of the reactive gases for a plurality of times,
with supply of the purge gas interposed therebetween, turn-around
of the gas to the lower part of the processing chamber below the
holder can be prevented. Therefore, the contact-gas area and the
gas flow passage capacity can be made small as much as possible,
the reactive gas can be supplied for a short time, and the residual
gas can be purged.
A fifteenth invention provides a method of manufacturing a
semiconductor device, including:
carrying a substrate into a processing chamber;
placing the substrate carried into the processing chamber on a
holder by lifting the holder;
processing the substrate by discharging gas by an exhaust duct
provided on the peripheral part of the holder while supplying the
gas to the substrate placed on the holder, and exhausting the gas
outside the processing chamber from an exhaust port provided below
an upper surface of the exhaust duct;
setting the substrate after processing possible to be carried out
by lowering the holder; and
carrying out the substrate after processing from the processing
chamber,
wherein in the step of lifting and lowering the holder, at least a
part of a member constituting the exhaust duct is lifted and
lowered together with the holder.
According to the present invention, the gas is exhausted by the
exhaust duct provided on the peripheral part of the holder, and the
gas thus exhausted by the exhaust duct is exhausted outside the
processing chamber by the exhaust port provided below the upper
surface of the exhaust duct. Therefore, the turn-around of the gas
to the lower part of the processing chamber below the holder can be
prevented. In addition, at least a part of the member constituting
the exhaust duct is lifted and lowered together with the holder.
Therefore, the substrate is not inhibited from carrying in/out the
processing chamber from the substrate carrying port. Further, at
least a part of the member constituting the exhaust duct is
liftably constituted, and when the substrate is processed and the
holder is lifted, a part of the exhaust duct is also lifted.
Therefore, the contact-gas area and the gas flow passage capacity
can be reduced.
A sixteenth invention provides the method of manufacturing the
semiconductor device according to the fifteenth invention, wherein
in the step of processing the substrate, two kinds or more of
reactive gases are alternately provided to the substrate for a
plurality of times, and supply of purge gas is interposed between
the alternate supply of the two kinds or more of the reactive
gases.
When a sequential process is thus performed, high purge efficiency
is required. However, even when such a process is performed, the
turn-around of the gas to the lower part of the processing chamber
below the holder can be prevented, and the contact-gas area and the
gas flow passage capacity can be reduced as much as possible.
Therefore, supply of the reactive gas and the purge of the residual
gas are possible for a short time.
A seventeenth invention provides the method of manufacturing the
semiconductor device according to the fifteenth invention, wherein
the step of processing the substrate includes the steps of:
adsorbing at least one kind of reactive gas on the substrate;
and
promoting a film deposition reaction by supplying reactive gas to
the adsorbed reactive gas different from this reactive gas.
When the sequential process is thus performed, high purge
efficiency is required, but even when such a sequential process is
performed, the turn-around of the gas to the lower part of the
processing chamber below the holder can be prevented, and the
contact-gas area and the gas flow passage capacity can be made
small as much as possible. Therefore, the supply of the reactive
gas and the purge of the residual gas are enabled in a short
time.
In addition, particularly in a case of the ALD, there is a
possibility that the film is deposited over an entire place where
the raw material in the processing chamber is adsorbed, thus
causing particles. Therefore, the contact-gas area of the gaseous
raw material is required to be made small as much as possible, and
simultaneously the flow passage capacity of the gaseous raw
material is also required to be made small as much as possible to
shorten the substitution time of two or more kinds of the gaseous
raw materials, and this can also be solved.
An eighteenth invention provides the method of manufacturing the
semiconductor device according to the fifteenth invention, wherein
the step of processing the substrate repeats for a plurality of
times the steps of:
supplying a first reactive gas to the substrate and adsorbing it on
the substrate;
purging it thereafter;
supplying a second reactive gas to the first reactive gas adsorbed
on the substrate, and promoting a film deposition reaction
thereafter; and
purging it thereafter.
When the sequential process is thus performed, the high purge
efficiency is required. However, even when such a process is
performed, the turn-around of the gas to the lower part of the
processing chamber below the holder can be prevented, and the
contact-gas area and the gas flow passage capacity can be made
small as much as possible. Therefore, the supply of the reactive
gas and the purge of the residual gas are enabled for a short
time.
In addition, particularly in the case of the ALD, there is a
possibility that the film is deposited over an entire place where
the raw material in the processing chamber is adsorbed, thus
causing particles. Therefore, the contact-gas area of the gaseous
raw material is required to be made small as much as possible, and
simultaneously the flow passage of the starting gas is also
required to be made small as much as possible to shorten the
substitution time of the two or more kinds of gaseous raw
materials, and this can also be solved.
A nineteenth invention provides the method of manufacturing the
semiconductor device according to the fifteenth invention, wherein
the step of processing the substrate includes the steps of:
decomposing at least one kind of reactive gas and depositing it on
a substrate; and
supplying reactive gas different from the aforementioned reactive
gas to the thin film thus deposited and modifying the thin
film.
When the sequential process is thus performed, high purge
efficiency is required. However, even when such a process is
performed, the turn-around of the gas to the lower part of the
processing chamber below the holder can be prevented, and the
contact-gas area and the gas flow passage capacity can be made
small as much as possible. Therefore, the supply of the reactive
gas and the purge of the residual gas are enabled in a short
time.
A twentieth invention provides the method of manufacturing the
semiconductor device according to the fifteenth invention, wherein
the step of processing the substrate repeats for a plurality of
times the steps of:
supplying a first reactive gas to a substrate and depositing a thin
film on the substrate;
purging it thereafter;
supplying a second reactive gas to the thin film deposited on the
substrate and modifying the thin film thereafter; and
purging it thereafter.
When the sequential process is thus performed, high purge
efficiency is required. However, even when such a process is
performed, the turn-around of the gas to the lower part of the
processing chamber below the holder can be prevented, and the
contact-gas area and the gas flow passage capacity can be made
small as much as possible. Therefore, the supply of the reactive
gas and the purge of the residual gas are enabled in a short
time.
ADVANTAGE OF THE INVENTION
According to the present invention, by reducing the contact-gas
area in the processing chamber and the flow passage capacity,
particles are prevented from being produced, and the throughput can
be improved. Accordingly, a high quality film with high
productivity can be formed.
BEST MODE FOR CARRYING OUT THE INVENTION
A process form, to which the present invention is applied, will be
explained hereunder with reference to the drawings. An explanation
is given here, with an ALD process given as an example, wherein a
gas which has been gasified from
Ru(EtCp).sub.2(bisethylcyclopentadienylruthenium), being a metal
containing raw material, is used as a first reactive gas, and
oxygen containing oxygen or nitrogen is used as a second reactive
gas, and a film deposition of a ruthenium film, being a metal film,
is performed.
FIG. 1 and FIG. 2 are sectional views for explaining a single wafer
type substrate processing apparatus according to a first
embodiment. FIG. 1 is a vertical sectional view when a substrate is
carried out and carried in, and FIG. 2 is a vertical sectional view
when the substrate is processed.
As shown in FIG. 1, the substrate processing apparatus includes a
processing chamber 1 for processing a substrate 2; a substrate
carrying port 10 provided on the sidewall 40 of the processing
chamber 1, for carrying in and carrying out the substrate 2; and a
susceptor 6 as a holder liftably provided in the processing chamber
1, for holding the substrate 2. Also included are supply ports 3
and 4 provided above the susceptor 6 for supplying gas into the
processing chamber 1, and an exhaust duct 35 provided on the
peripheral part of the susceptor 6 for discharging the gas supplied
into the processing chamber 1. Further, included is an exhaust port
5 for exhausting the gas discharged by the exhaust duct 35 to the
outside the processing chamber 1.
The processing chamber 1 is flatly constructed by an upper
container 46 and a lower container 47 which are circular in
section. This processing chamber 1 is constructed to process the
substrate 2 such as one sheet of silicon substrate (silicon wafer)
by a sealed flat inner space. The upper container 46 and the lower
container 47 are constructed by aluminum and stainless, for
example.
The substrate carrying port 10 is provided on one sidewall of the
lower container 47. A transfer chamber 9a is provided in an opening
of an extension part extended outside from this substrate carrying
port 10 through a gate valve 11. A transfer robot 45 as a carrying
means is provided in the transfer chamber 9a. By this transfer
robot 45, the substrate 2 can be carried from the transfer chamber
9a to the processing chamber 1 or from the processing chamber 1 to
the transfer chamber 9a through the substrate carrying port 10,
with the gate valve 11 opened. Note that purge gas can be supplied
into the substrate carrying port 10 through a valve 19. Inert gas
such as Ar, N.sub.2, He can be given as the purge gas.
A susceptor 6, being discoidal, is provided in the processing
chamber 1, and the substrate 2 is held thereon in an almost
horizontal state. The susceptor 6 has a heater 6a built therein
such as a ceramics heater controlled by a temperature controller
21, and the substrate 2 is heated to a specified temperature. Also,
the susceptor 6 is constructed so as to support the exhaust duct 35
on the peripheral part of the substrate 2 held by the susceptor 6.
The susceptor 6 has a support shaft 59. The support shaft 59 is
inserted in a vertical direction from a thorough hole 58 provided
in a bottom center of the lower container 47 of the processing
chamber 1, so that the susceptor 6 can be vertically moved by a
lifting/lowering mechanism 9. The substrate 2 is carried at a
substrate carrying position (position shown in FIG. 1) where the
susceptor 6 is in a lower part, and a film deposition processing is
performed at a substrate processing position (position shown in
FIG. 2) where the susceptor is in an upper part. When the susceptor
6 supporting the exhaust duct 35 is located at the aforementioned
substrate processing position, a processing chamber upper part 1a
above the exhaust duct 35 and a processing chamber lower part 1b
below the exhaust duct 35 are vertically formed in the processing
chamber 1, by the exhaust duct 35 and the susceptor 6 whereby
inside of the processing chamber 1 is vertically partitioned. Note
that the purge gas can be supplied to the through hole 58 via the
valve 18. The inert gas such as Ar, N.sub.2, and He can be given as
the inert gas. The susceptor is constituted of quartz, carbon,
ceramics, silicon carbide (SiC), aluminum oxide (Al.sub.2O.sub.3),
or aluminum nitride (AlN), for example.
The gas supply ports 3 and 4 are provided in the upper container 46
and therefore are provided above the susceptor 6. A shower plate 8a
having a plurality of holes is provided in the center of the upper
container 46 that faces the susceptor 6, and the gas supply ports 3
and 4 are positioned in the upper part of this shower plate 8a. The
gas supply ports 3 and 4 are adjacently provided. The gas supplied
from the gas supply ports 3 and 4 is supplied to a space above the
shower plate 8a, and is supplied on the substrate 2 in a state of a
shower from a plurality of holes of the shower plate 8a, then flows
on the substrate 2 in a diameter direction of the substrate, and is
exhausted toward the exhaust port 5 from the peripheral part of the
substrate 2 through the exhaust duct 35 as will be described later
(flowing type in the diameter direction). Here, the flowing type in
the diameter direction refers to a type of supplying the gas in a
vertical direction to a substrate surface from the gas supply port
provided in the upper part of the substrate, allowing the gas to
flow on the substrate in the diameter direction of the substrate,
and exhausting the gas from the peripheral part of the substrate
toward the exhaust port.
Lines of two systems for supplying the gas are connected to the gas
supply ports 3 and 4. A line connected to a gas supply port 3,
which is one of them, is the line for supplying the first reactive
gas, namely, a Ru(EtCp).sub.2 supply line 14 for supplying
Ru(EtCp).sub.2(bisethylcyclopentadienylruthenium), being an organic
liquid raw material used in depositing a metal film such as a
ruthenium film. Note that as described later, the Ru(EtCp).sub.2
supply line 14 selectively supplies the first reactive gas or the
purge gas into the upper part of the processing chamber 1a from the
gas supply port 3.
Another line connected to other gas supply port 4 is a line for
supplying a second reactive gas, namely an oxygen supply line 15
for supplying a gas containing oxygen or nitrogen, being a gas with
high reactivity to the organic liquid raw material, such as oxygen.
Note that as described later, the oxygen supply line 15 selectively
supplies the second reactive gas or the purge gas into the upper
part of the processing chamber 1a from the gas supply port 4.
The Ru(EtCp).sub.2 supply line 14 is provided with a liquid flow
late control device 23 for controlling a flow rate of
Ru(EtCp).sub.2, being the liquid raw material, in a liquid state; a
vaporizer 25 for vaporizing the Ru(EtCp).sub.2 liquid whose flow
rate is controlled; and a valve 12 for stopping the supply of
vaporized Ru(EtCp).sub.2 to the line 14. An Ar supply line 57 is
connected on the downstream side of the valve 12 of this
Ru(EtCp).sub.2 supply line 14, and an Ar gas whose flow rate is
controlled by a flow rate control device 22 can be supplied to the
Ru(EtCp).sub.2 supply line 14 through a valve 16.
Note that instead of Ar, the inert gas such as N.sub.2 and He may
be supplied from the Ar supply line 57.
The above-described structure allows the following three options to
be taken for introducing the gas to the supply port 3.
(1) By opening the valve 12 of the Ru(EtCp).sub.2 supply line 14
and closing the valve 16 of the Ar supply line 57, only
Ru(EtCp).sub.2 gas vaporized by the vaporizer 25 is independently
introduced to the supply port 3 from the Ru(EtCp).sub.2 supply line
14.
(2) Further, by opening the valve 16 of the Ar supply line 57,
mixed gas of the Ru(EtCp).sub.2 gas and Ar gas is introduced to the
supply port 3 from the Ru(EtCp).sub.2 supply line 14.
(3) By stopping the supply of the Ru(EtCp).sub.2 gas from the
vaporizer 25, only the Ar gas is independently introduced to the
supply port 3 from the Ru(EtCp).sub.2 supply line 14.
The oxygen supply line 15 is provided with a flow rate control
device 24 for controlling the flow rate of oxygen; a remote plasma
unit 33 for activating the oxygen whose flow rate is controlled;
and the valve 13 for stopping the supply of the activated oxygen to
the line 15. The aforementioned Ar supply line 57 is branched by a
branch line 57a and connected on the downstream side of the valve
13 of this oxygen supply line 15, so that the Ar gas whose flow
rate is controlled by the flow rate control device 22 can be
supplied to the oxygen supply line 15 through a valve 17.
The above-described structure allows the following three options to
be taken for introducing the gas to the supply port 4.
(1) By opening the valve 13 of the oxygen supply line 15 and by
closing the valve 17 of the branch line, only the oxygen (referred
to as activated oxygen hereafter) activated by the remote plasma
unit 33 is independently introduced to the supply port 4.
(2) Further, by opening the valve 17 of the branch line 57a, the
mixed gas of the activated oxygen and the Ar gas is introduced to
the supply port 4 from the oxygen supply line 15.
(3) By stopping the supply of the activated oxygen from the remote
plasma unit 33, only the Ar gas is independently introduced to the
supply port 4 from the oxygen supply line 15.
The exhaust duct 35 is provided on the peripheral part of the
susceptor 6, and when the substrate is processed, the gas supplied
into the upper part of the processing chamber 1a above the
susceptor is discharged from the peripheral part of the susceptor.
Whereby the gas is exhausted to the outside the processing chamber
1, without being flown to the lower part 1b of the processing
chamber (see FIG. 2). This exhaust duct 35 is constructed by a
plate 7 having a hollow part (plate buffer) 27 that communicates
with the upper part 1 of the processing chamber. The plate 7 has a
discharge port 26 and a plate exhaust port 28, and the gas supplied
into the upper part 1a of the processing chamber is discharged into
the hollow part 27 from the discharge port 26, and the gas thus
discharged into the hollow part 27 is exhausted from the plate
exhaust port 28.
A part of the plate 7 is placed on the susceptor 6, so as to cover
at least a part of the upper surface of the susceptor 6. Thus, the
exhaust duct 35 constructed by the plate 7 is linked with a
movement of the susceptor 6 and is lifted and lowered together with
the susceptor 6. In addition, since a part of the plate 7 covers at
least a part of the upper surface of the susceptor 6, deposition of
the film on a part thus covered can be prevented, and a gap between
the susceptor 6 and the plate 7 formed when the plate 7 is not
placed on the susceptor 6 to cover the upper surface of the
susceptor 6 can be closed, and turn-around of the gas to the
backside of the susceptor 6 from between the sidewall of the
susceptor 6 and the plate 7 can be prevented.
The exhaust duct 35 (hollow part 27) is disposed at a position not
facing the substrate carrying port 10, for example, below the
substrate carrying port 10 (see FIG. 1). Also, when the substrate
is processed, the exhaust duct 35 is disposed at a position facing
a part (upper part) of the substrate carrying port 10, namely, at a
position closing at least a part of the substrate carrying port 10
(see FIG. 2). Further, when the substrate is processed, the exhaust
duct 35 is provided so as to close the gap between the sidewall 40
of the processing chamber and the sidewall 60 of the susceptor.
When the substrate is carried in and out, the exhaust duct 35 is
disposed below the substrate carrying port 10 so that the exhaust
duct does not cause obstruction for carrying in and out the
substrate. Also, when the substrate is processed, the exhaust duct
35 is disposed at a position closing at least a part of the
substrate carrying port 10 to make the capacity of an entire body
of the processing chamber small by overlapping a part of the
exhaust duct 35 on the substrate carrying port 10 and decreasing
the height of the processing chamber by this overlapped portion,
and also to reduce a contact-gas area by closing the substrate
carrying port 10 and preventing the turn-around of the gas. Also,
when the substrate is processed, the exhaust duct 35 is provided so
as to close the gap between the sidewall 40 of the processing
chamber and the sidewall 60 of the susceptor, in order to prevent
the gas from flowing to the lower part 1b of the processing chamber
from the upper part 1a of the processing chamber by interrupting
the flow passage to the lower part 1b of the processing
chamber.
The exhaust duct will be explained in detail by using FIG. 3 and
FIG. 4. FIG. 3 is a projection view and a sectional view of the
plate 7, (a) is a plan view, (b) is a side view, (c) is a front
view, (d) is a sectional view taken along the line A-A, (c) is a
sectional view taken along the line B-B, and FIG. 4 is a partially
broken perspective view of the plate 7.
The plate 7 constituting the exhaust duct 35 has a shape of a flat
annular body as a whole, and is provided on the peripheral part of
a flat discoidal susceptor 6. The hollow part 27 of the plate 7 is
annularly provided below the upper surface of a part placed on the
susceptor 6 of the plate 7 and at a sidewall peripheral position of
the susceptor 6, so as to surround the susceptor 6 (see FIG.
4).
The plate 7 having the hollow part 27 is constructed by a first
plate 37 and a second plate 36, and they are integrally formed. The
first plate 37 has an annular recessed part 37a with an upper part
opened. The recessed part 37a forms an exhaust passage for
introducing to the exhaust port 5 the gas supplied into the upper
part 1a of the processing chamber when the substrate is processed.
The second plate 36 is formed of a ring plate whereby a part of the
opening of the recessed part 37a of the first plate 37 is covered
and the hollow part 27 is formed, and the substrate 2 placed on the
susceptor 6 is fit into a hole 34 of the center.
Note that the second plate 36 is provided around the substrate 2,
and controls a gas flow flowing onto the substrate 2. Here, the
plate 7 is supported on the peripheral part of the susceptor 6 in
such a way as overhung over the sidewall 40 of the processing
chamber from the susceptor 6. In addition, the plate 7 is provided
so that its surface is flush with the surface of the substrate 2.
Thus, the second plate 36 has also a function as a rectifying plate
capable of parallely and uniformly supplying the reactive gas or
the purge gas (referred to as simply gas in some cases) onto the
surface of the substrate.
A plate, whose outer diameter is slightly smaller than a diameter
of an outer sidewall (inner wall face) of the recessed part 37a of
the first plate 37, and whose inner diameter is smaller than a
diameter of an inner sidewall of the recessed part 37a, is used for
the second plate 36. This second plate 36 is concentrically placed
on the first plate 37. By this structure, the second plate 36 is
not completely overlapped on an opening upper part of the recessed
part 37a of the first plate 37 (partially overlapped), and the
second plate 36 has an appearance of being deviated inwardly in a
diameter direction with respect to the opening upper part of the
recessed part 37a of the first plate 37. Accordingly, the second
plate 36 is placed only on an upper side of the inner sidewall of
the recessed part 37a of the first plate 37. Note that an outer
peripheral part of the second plate 36 is called a plate outside
part 36a and an inner peripheral part of the second plate 36 is
called a plate inside part 36b, with a part placed on an upper side
of the inner sidewall of the recessed part 37a as a border. As
described above, by the deviation of the second plate 36 with
respect to the opening upper part of the recessed part 37a, an
annular gap is formed on the upper side of the outer peripheral
sidewall of the hollow part 27 formed by being covered by the plate
outside part 36a of the second plate 36, and this annular gap
becomes an annular discharge port 26 formed on the upper surface of
the plate 7 (see FIGS. 3(a) and (e)). In addition, the plate inside
part 36b of the second plate 36 swelling inward from the inner
sidewall of the recessed part 37a becomes a part of the plate 7
placed on the outer peripheral upper surface of the susceptor
6.
Note that the discharge port 26 has not only the function of
discharging into the hollow part 27 the gas supplied into the upper
part 1a of the processing chamber, but also the function of
adjusting conductance for equalizing a gas flow onto the silicon
substrate 2. Namely, the discharge port 26 controls a gas quantity
discharged into the hollow part 27 of the plate 7 through this
discharge port 26, from the upper part 1a of the processing chamber
above the plate 7, and controls a gas pressure of the gas supplied
onto the substrate 2, thereby equalizing a pressure distribution on
the substrate 2. The discharge conductance of this discharge port
26 can be adjusted by deflecting the position of the second plate
36 and changing a shape of the plate outside part 36a of the second
plate 36.
The plate exhaust port 28 is provided on the outer sidewall of the
first plate 37. This plate exhaust port 28 is formed into a
circular shape, below the discharge port 26 and at a part facing
the exhaust port 5, namely at a lower outer sidewall of the first
plate 37, out of the whole peripheral part of the outer sidewall of
the first plate 37, so that the gas discharged into the hollow part
27 from the discharge port 26 is exhausted to the exhaust port 5
(see FIGS. 3(b) and (d)). Note that the aforementioned plate 7 is
constituted of quartz and ceramics series (AlN, Al.sub.2O.sub.3,
SiC), etc, for example.
The exhaust port 5 for exhausting the gas to the outside the
processing chamber 1 is provided on the other side of the opposite
side of the substrate carrying port 10 provided on one end side of
the lower container 47, and below the upper surface of the exhaust
duct 35, when the substrate is processed (see FIG. 2). This exhaust
port 5 is connected to a vacuum pump 51, and the gas exhausted from
the exhaust duct 35 is exhausted to the outside the processing
chamber 1. Inside the processing chamber 1 can be controlled to a
prescribed pressure by a pressure controller 20 as needed.
In addition, a thrust-up pin 8 for temporarily holding the
substrate 2 when the substrate is carried in and out is provided on
the bottom part of the lower part 1b of the processing chamber of
the lower container 47. This thrust-up pin 8 is provided so as to
pass through the through hole provided in the susceptor 6 and a
heater 6a. The thrust-up pin 8 projects from the through hole and
holds the substrate 2. At a substrate processing position of the
susceptor (FIG. 2), the thrust-up pin 8 retracts from the through
hole, and the substrate is held on the susceptor 6.
Here, the flow of the gas when the substrate is processed will be
explained.
The gas supplied from the gas supply ports 3 and 4 is dispersed by
a shower plate 8a, then is supplied onto the silicon substrate 2 in
the processing chamber 1a, and radially flows on the silicon
substrate 2 outward in the diameter direction of the substrate.
Then, it radially flows outward in the diameter direction on the
plate 7 whereby an upper side of the outer peripheral part of the
susceptor 6 is covered, and is discharged into the annular hollow
part 27 from the discharge port 26 provided on the upper surface of
the plate 7. The gas thus discharged flows in the hollow part 27 in
a peripheral direction of the susceptor, and is exhausted from the
plate exhaust port 28 to the exhaust port 5. Thus, turn-around of
the gaseous raw material into the processing chamber 1b, namely to
the backside wall of the susceptor 6 and to the bottom part 42 of
the processing chamber 1 can be prevented. Simultaneously at this
time, the valves 18 and 19 are opened and the carrying port 10, the
through hole 58, the bottom part of the processing chamber 1, the
backside wall of the susceptor 6 are purged by the purge gas, and
the turn-around of the gaseous raw material to the lower part 1b of
the processing chamber is prevented.
Note that if a small amount of gaseous raw material is turned
around to the lower part 1b of the processing chamber, etc, the
small amount of gaseous raw material thus invaded is diluted to a
level not affecting adversely, and is exhausted from the exhaust
port 5.
Note that in the substrate processing apparatus of this embodiment,
the gas flow passage capacity at the time of processing the
substrate is decreased down from the volume of the entire body of
the processing chamber 1, by limiting it to the upper part 1a of
the processing chamber formed between the upper surfaces of the
susceptor 6 and the plate 7 and the inner wall surface of the upper
container 46, and the hollow part 27 of the plate 7.
As described above, the substrate processing apparatus according to
this embodiment is constituted.
Next, as one step of the steps of manufacturing a semiconductor
device by using the aforementioned substrate processing apparatus,
a method of processing a substrate will be explained. Here, as
described above, an explanation is given, with an ALD process for
depositing a ruthenium film on a silicon substrate, taken as an
example.
In FIG. 1, the gate valve 11 is opened, with the susceptor 6
lowered to a carry-in/carry-out position. By a transfer robot 45 in
a transfer chamber 9a, one sheet of silicon substrate 2 is carried
into the processing chamber 1 through a carrying port 10, and is
placed and held on the thrust-up pin 8. After closing the gate
valve 11, the susceptor 6 is lifted to a substrate processing
position by a lifting/lowering mechanism 9. At this time, the
substrate 2 is automatically placed on the susceptor 6 from the
thrust-up pin 8. FIG. 2 shows this state. Note that when the
susceptor 6 is lifted to the substrate processing position, the
upper part 1a of the processing chamber is formed between the upper
surfaces of the susceptor 6 and the plate 7 and the inner wall
surface of the upper container 46, and the lower part 1b of the
processing chamber is formed between the lower surfaces of the
susceptor 6 and the plate 7, and the inner wall surface of the
lower container 47.
The heater 6a is controlled by a temperature controller 21 to heat
the susceptor 6, and the silicon substrate 2 is heated for a fixed
time period. The valves 18 and 19 are opened before depositing the
film, and a flow in one direction by the purge gas (such as Ar) is
formed toward the exhaust port 5, passing through the carrying port
10, the through hole 58, and the lower part 1b of the processing
chamber, and an invasion of the gaseous raw material (reactive gas)
at the time of depositing the film is prevented. The pressure in
the processing chamber 1 is controlled by a pressure controller 20.
After the silicon substrate 2 is heated to a prescribed temperature
and the pressure is stabilized, the film is started to be
deposited. A film deposition is composed of the following four
steps, and a plurality of cycles are repeated until the film of a
desired thickness is deposited, with four steps set as one
cycle.
In step 1, the valve 12 is opened, and the raw material
Ru(EtCp).sub.2, whose flow rate is controlled by a liquid flow rate
control device 23, is vaporized by a vaporizer 25, and is passed
through a shower plate 8a through the supply port 3 from a
Ru(EtCp).sub.2 supply line 14, and is introduced into the
processing chamber 1 in a state of shower. Note that at this time,
a reverse flow of Ru(EtCp).sub.2 gas into an oxygen supply line 15
may be prevented by opening the valve 17 and supplying the purge
gas into the oxygen supply line 15. The Ru(EtCp).sub.2 gas is
supplied onto the silicon substrate 2, and is adsorbed on its
surface. Surplus gas flows into the hollow part 27 of the plate 7
from a discharge port 26 provided on the upper surface of the plate
7, then is exhausted by a plate exhaust port 28, and is exhausted
to the outside the processing chamber 1 from the exhaust port
5.
In step 2, the valve 12 is closed and the valve 16 is opened, and
the Ar gas, whose flow rate is controlled by the flow rate control
device 22, is passed through the shower plate 8a through the supply
port 3 from the Ru(EtCp).sub.2 supply line 14, and is supplied into
the processing chamber 1 in a state of shower. The Ru(EtCp).sub.2
gas remained in the Ru(EtCp).sub.2 supply line 14 and the
processing chamber 1 is purged by Ar and flows through the hollow
part 27 of the plate 7 from the discharge port 26 provided on the
upper surface of the plate 7, and is exhausted by the plate exhaust
port 28, and is exhausted to the outside the processing chamber 1
from the exhaust port 5.
In step 3, the valve 16 is closed and the valve 13 is opened, and
oxygen, whose flow rate is controlled by a flow rate control device
24, is activated by a remote plasma unit 33. Activated oxygen is
passed through the shower plate 8a from an oxygen supply line 15
through a supply port 4, and is supplied into the processing
chamber 1 in a state of shower. Note that the reverse flow of the
gas (activated oxygen) into the Ru(EtCp).sub.2 supply line 14 may
be prevented by continuously supplying the Ar gas to the
Ru(EtCp).sub.2 supply line 14 without closing the valve 16 (by
maintaining an opened state). In some cases, without using the
remote plasma unit 33, the oxygen is supplied in a state of not
being activated. The activated oxygen is supplied onto the silicon
substrate 2, and reacts with Ru(EtCp).sub.2 adsorbed on the silicon
substrate 2 (by a surface reaction), and a ruthenium film is
thereby formed. The surplus gas flows through the hollow part 27 of
the plate 7 from the discharge port 26 provided on the upper
surface of the plate 7, then is exhausted from the plate exhaust
port 28, and is exhausted to the outside the processing chamber 1
from the exhaust port 5.
In step 4, the valve 13 is closed and the valve 17 is opened, and
the Ar gas, whose flow rate is controlled by the flow rate control
device 22, is passed through the shower plate 8a from the oxygen
supply line 15 through the supply port 4, and is supplied into the
processing chamber 1 in a state of shower. The oxygen remained in
the oxygen supply line and in the processing chamber 1 is purged by
Ar and flows through a plate buffer (hollow part) 27 from the
discharge port 26 provided on the surface of the plate 7, then is
exhausted from the plate exhaust port 28, and is exhausted to the
outside the processing chamber 1 from the exhaust port 5.
A plurality of cycles are repeated until the ruthenium film of a
desired thickness is deposited, with the aforementioned four steps
as one cycle. It is desirable to set the time required for the
steps 1 to 4 to be 1 second or less for improving throughput. After
depositing the film, the susceptor 6 is lowered to a
carry-in/carry-out position by the lifting/lowering mechanism 9,
and after the gate valve 11 is opened, the silicon substrate 2 is
passed through the carrying port 10 and is carried out to the
transfer chamber 9a by the transfer robot 45.
A processing condition is preferably set in a range of temperature:
200 to 500.degree. C., pressure: 0.1 to 10 Torr (13.3 to 1330 Pa),
total flow rate of the gas supplied to the processing chamber: 0.1
to 2 slm, and film thickness: 1 to 50 nm.
Note that the temperature of the substrate and the pressure in the
processing chamber in each step are controlled by the temperature
controller 21, the pressure controller 20, each valve 12 to 13, 16
to 19, the vaporizer 25, the remote plasma unit 33, and the flow
rate control devices 22 to 24, etc, and an integrated control is
applied to the movement of each part constituting the substrate
processing apparatus by a controller 50.
An action of the aforementioned embodiment will be explained
hereunder.
First, deposition of the film on the bottom part 42 of the
processing chamber, etc, can be prevented. This is because the
turn-around of the gas to the lower part 1b of the processing
chamber is prevented by exhaustion by the hollow part 27 of the
plate 7, and a contact between the gas and the inner wall surface
is reduced in the lower part 1b of the processing chamber. Note
that even if a small amount of gaseous raw material turns around to
the lower part 1b of the processing chamber, etc, the small amount
of gaseous raw material thus turned around is diluted by the purge
gas supplied into the lower part 1b of the processing chamber by
the carrying port 10 and the through hole 58, to the level not
allowing film deposition to occur, and is exhausted from the
exhaust port 5. Thus, the deposition of the film on the bottom part
42 of the processing chamber, a driving part, the carrying port 10,
and the gate valve 11, etc, can be significantly reduced, and
particles are prevented from being produced, which is caused by
peeling-off of a deposited film when the driving part is
actuated.
When the plate 7 having the hollow part 27 is not provided, the gas
turns around to the bottom part of the processing chamber, etc, to
allow the film to be deposited thereon. Therefore, when the film of
more than allowable thickness is deposited, the entire body of the
processing chamber or the lower container 47 must be replaced.
However, if the processing chamber 1 needs to be replaced, loss of
time and cost is enormous. It can be considered that a cover for
preventing the deposition is separately set in the bottom part 42
of the processing chamber. However, it is difficult to set the
cover in the driving part where the susceptor 6 is lifted and
lowered. Therefore, the cover is not practical. In this point, this
embodiment efficiently prevents the film to be deposited on the
bottom part of the processing chamber, thus eliminating the
necessity of replacement of the processing chamber, improving
productivity of the device, and reducing a device cost.
Secondly, the film deposition on the susceptor 6 can be prevented.
The susceptor 6 has a heater 6a for heating the substrate 2, and
frequently has a higher temperature than the temperature of the
substrate, and the film is also deposited on this susceptor 6. The
deposited film is accumulated, and is peeled off in the end, to
become a particle source, thus reducing a yield ratio of a
semiconductor. However, according to this embodiment, a part of the
plate 7 (inside part 36b of the plate) covers the upper side of the
peripheral part of the susceptor 6, thus making it possible to
prevent the deposition of the film on the outer peripheral part of
the susceptor 6. Even if a small amount of deposition proceeds on
the susceptor 6, maintenance by gas cleaning is performed before
the deposited film peels-off, when the film can be removed by the
gas cleaning. However, in this case, a film depositing progression
on the susceptor 6 is slow, because a part of the plate 7 covers
the upper side of the outer peripheral part of the susceptor 6.
Therefore a maintenance cycle can be prolonged. Accordingly, a rate
of operation of the device is increased, thereby improving the
productivity. Meanwhile, when it is difficult to remove the film by
gas cleaning, the susceptor 6 is replaced. In this case also, since
a part of the plate 7 covers the upper side of the outer peripheral
part of the susceptor 6, the progression of the film deposition is
slow, the cycle of replacement of the susceptor is prolonged, and a
service life can be prolonged. Accordingly, the rate of operation
of the device is increased, thus improving the productivity and
reducing the device cost.
Further the film is also deposited on the plate 7. However, in this
case, without replacing the susceptor 6, only the plate 7 may be
replaced. Therefore, the time and cost required for replacement can
be largely reduced.
Thirdly, the contact-gas area and the flow passage capacity of the
gas supplied from the supply ports 3 and 4 can be reduced. This is
because the plate 7 having the hollow part 27 is set on the outer
peripheral part of the susceptor 6, and the gap between the
sidewall 40 of the processing chamber and the sidewall 60 of the
susceptor is closed by the first plate 37 constituting the hollow
part 27, and the gas is exhausted from the hollow part 27 to the
exhaust port 5 without passing through the lower part 1b of the
processing chamber.
By reducing the contact-gas area in this way, a deposition amount
of the gaseous raw material in the processing chamber is reduced,
and the particles are prevented from being produced.
In addition, by reducing the flow passage capacity, an amount of an
existence of the gaseous raw material itself in the processing
chamber can be reduced, and the amount of the gaseous raw material
to be supplied and the amount of a residual gaseous raw material
are reduced. Therefore, the gaseous raw material can be efficiently
supplied, or the residual gas can be purged. Accordingly, in the
film deposition method wherein two kinds of reactive gases are
alternately supplied, supply of the gaseous raw material and purge
of the residual raw material can be performed in a short time.
As a result, the semiconductor manufacturing apparatus with high
yield ratio, high throughput, and excellent in productivity can be
realized.
Fourthly, the volume of the entire body of the processing chamber
can be made small. If the entire body of the plate 7 having the
hollow part 27 is fixed to the substrate processing position, when
the substrate is carried in and carried out, the substrate carrying
port 10 is required to be disposed below the plate 7, so that the
plate 7 is not overlapped on the substrate carrying port 10 to
permit the substrate to be carried in and carried out the
processing chamber. A problem involved therein is that the entire
body of the processing chamber becomes higher, thus making the
volume of the entire body of the processing chamber larger.
However, in this embodiment, the plate 7 is liftably provided, and
therefore when the substrate is carried in and carried out, the
plate 7 can be disposed on the sidewall of the susceptor 6, below
the substrate carrying port 10, and when the substrate is
processed, the plate 7 can be disposed so as to overlap on the
substrate carrying port 10, thus making it possible to decrease the
height of the entire body of the processing chamber by this
overlapped portion. Therefore, the volume of the entire body of the
processing chamber can be made small, and purge efficiency can
thereby be further enhanced.
Note that in this embodiment, Ru(EtCp).sub.2, being the metal
containing raw material, is used as the first reactive gas, and
oxygen O.sub.2, being the gas containing oxygen or nitrogen, is
used as the second reactive gas. However, the gas used in the
present invention can be suitably selected from various kinds in
accordance with a purpose of use. For example, the metal containing
gaseous raw material includes any one of Si, Al, Ti, Sr, Y, Zr, Nb,
Sn, Ba, La, Hf, Ta, Ir, Pt, W, Pb, and Bi other than the metal
containing Ru. Also, the gas containing oxygen or nitrogen includes
O.sub.3, NO, N.sub.2O, H.sub.2O, H.sub.2O.sub.2, N.sub.2, NH.sub.3,
and N.sub.2H.sub.6 other than O.sub.2, and radical species or ionic
species generated by activating any one of the aforementioned gases
by an activating means.
In addition, as the film deposition method according to this
embodiment, the ALD has been explained, and the cyclic MOCVD is
also referred to. However of course this embodiment can also be
utilized in a MOCVD (Metal Organic Chemical Vapor Deposition)
whereby the film is deposited by simultaneously supplying the metal
containing raw material and the gas containing oxygen or nitrogen,
or by thermally decomposing the metal containing raw material.
Also, in the aforementioned embodiment, explanation has been given
to a case that the discharge port 26 of the plate 7 having the
hollow part 27 is not formed, with an upper part of the hollow part
27 fully opened, but is formed in such a way that it is narrowed
down to be a slit shape, so that the discharge port 26 has a
function of conductance adjustment. Also, explanation has been
given to a case that a part of the plate 7 covers only a part of
the susceptor 6, and the plate 7 is separately constituted from the
susceptor 6. Further, explanation has been given to a case that the
plate exhaust port 28 is formed on the outer sidewall of the plate
7. However, the present invention is not limited thereto, and
various modifications are possible.
For example, the plate as shown in FIG. 5(a) exemplifies a mode
that the discharge port 26 of the plate 7 having the hollow part 27
does not have the function of conductance adjustment. Namely, this
shows the discharge port 26 wherein the recessed part 37a of the
first plate 37 is not covered by the second plate 36, and the
opening upper part of the recessed part 37a is made fully opened.
In a case of the ALD, wherein adsorption of the gas on the silicon
substrate 2 is mainly performed and an influence of gas flow is
small, it may take a mode of not performing the conductance
adjustment. Therefore, the mode thus exemplified is preferably
applied to the ALD.
Note that a ring-shaped discharge port 26 is not equally set to
have the same width over the whole peripheral part, but the
conductance on the exhaust port side and on the opposite side
thereto may be changed, by changing a size (width) of the slit
forming the discharge port on the exhaust port side and a size
(width) of the slit forming the discharge port on the opposite side
of the discharge port. This is effective when gas pressure is
different between the exhaust port side and the opposite side
thereto and a pressure distribution on the substrate can not be
equalized.
Also, a modified example of the plate shown in FIG. 5(b) shows a
case that a part of the plate 7 covers an entire body of the
surface of the susceptor 6. When the entire body of the surface of
the susceptor 6 is covered, film deposition on the susceptor 6 can
be further prevented. However, in this case, heat conductivity from
the heater 6a in the susceptor 6 is poor, and therefore selection
in accordance with the film deposition method is required. For
example, although temperature dependency is higher in the cyclic
MOCVD, the temperature dependency is not so high in the ALD.
Accordingly, it is preferable to apply this modified example to the
ALD.
Further, in the example shown in FIG. 3(b) and FIG. 3(d), the plate
discharge port 28 is provided only on the outer sidewall of the
first plate 37. However, as shown in FIG. 5(c), the plate discharge
port 28 may be provided in a range from the outer sidewall to a
bottom surface of the first plate 37, or may be provided only on
the bottom surface.
Also, in FIG. 3 and FIG. 4, the diameter of a hole provided in the
center part of the second plate 36 is made approximately same as
the diameter of the silicon substrate 2. However, as is shown in a
third embodiment as will be described later, the diameter of the
hole provided in the center part of the second plate may be made
smaller than the diameter of the silicon substrate 2, and the
second plate 36 may be placed so as to cover the outer peripheral
part of the silicon substrate 2. With such a structure, film
deposition on the outer peripheral part of the silicon substrate
can be prevented, which is required in some steps of manufacturing
the semiconductor device, such as a deposition step of the film of
a metal system such as Ru.
Also, in the modified example of the plate as shown in FIG. 6, the
plate 7 having the hollow part 6b is integrally formed with a main
body 6c of the susceptor 6. When the susceptor 6 and the plate 7
(exhaust duct) are thus integrally formed, the structure can be
simplified. Note that in this case, AlN is preferable as a material
of the susceptor. In addition, in this modified example, an opening
area of the discharge port 26 on the opposite side of the exhaust
port 5 is made larger than the opening area of the discharge port
26 on the exhaust port 5 side, and the conductance of the discharge
port 26 on the opposite side of the exhaust port 5 (plate exhaust
port 28) is made larger than the conductance of the discharge port
26 on the exhaust port 5 side.
Incidentally, as described above, in the first embodiment, the gap
between the sidewall 40 of the processing chamber and the outer
peripheral sidewall 60 of the susceptor 6 is closed by the plate 7.
Therefore, it is possible to prevent the turn-around of the gas
supplied to the upper part 1a of the processing chamber, to the
lower part 1b of the processing chamber when the substrate is
processed. However, in this case also, a part of the plate 7 is
placed on the susceptor 6, so as to be lifted and lowered in the
processing chamber 1 together with the susceptor 6. Therefore, the
gap between the sidewall 40 of the processing chamber and the
sidewall of the plate 7 must be secured, thus making it impossible
to avoid the formation of the gap. Therefore, when the substrate is
processed, it appears that some of the gas supplied to the upper
part 1a of the processing chamber is not discharged into the hollow
part 27 of the plate 7 constituting the exhaust duct 35, but is
turned around to the lower part 1b of the processing chamber
through this gap.
In this point, the following knowledge is obtained. Namely, when
the plate is carried to the substrate processing position, the gap
formed between the sidewall of the plate and the sidewall of the
processing chamber is closed at the substrate processing position,
thus eliminating the turn-around of the aforementioned some gases.
Then, in order to realize this structure, it is found that the
plate is made separable, one of the plates thus separated is
liftably provided, and the other plate is held at the substrate
processing position, and the gap formed between one of the plates
and the sidewall of the processing chamber is closed from above by
other plate when one of the plates is carried to the substrate
processing position.
FIG. 7 and FIG. 8 are sectional views of the single wafer type
substrate processing apparatus according to a second embodiment,
wherein by using such a separable plate, it is possible to prevent
the turn-around of the aforementioned some of the gases. FIG. 7 is
a vertical sectional view at the time of carrying-in and
carrying-out the substrate, and FIG. 8 is a vertical sectional view
at the time of processing the substrate. The second embodiment has
basically the same structure as that of the first embodiment, and
the same sings and numerals are assigned to the same parts, and
explanation therefore is omitted. A different point from the first
embodiment is that the plate 7 having the hollow part 27
constituting the exhaust duct 35 of the first embodiment is made
separable. Mainly the different point from the first embodiment
will be explained hereunder in detail.
The exhaust duct 35 is constructed by the plate 7 having the hollow
part 27 that communicates with the processing chamber 1, and the
plate 7 is composed of a first plate 39 having a recessed part 39a
and a second plate 29 covering the recessed part 39a of the first
plate 39, and they are made separable.
This first plate 39 is composed of the recessed part 39a and a flat
plate part 39b. The recessed part 39a is provided so as to close
the gap between the sidewall 60 of the susceptor 6 and the sidewall
40 of the processing chamber 1, and an exhaust passage is formed
for introducing to the exhaust port the gas supplied into the upper
part 1a of the processing chamber when the substrate is processed.
The recessed part 39a, with an upper part opened, has the plate
exhaust port 28 at a position corresponding to the discharge port
5. The flat plate part 39b is placed on the susceptor 6, in a state
of covering the entire body of the susceptor 6, and is constructed
by a discoidal plate for preventing the deposition of the film on
the susceptor 6. The first plate 39, with its flat plate part 39b
placed on the susceptor 6, is liftably provided together with the
susceptor 6.
The second plate 29 is held at the substrate processing position.
This second plate 29 is constructed by a sheet of circular plate in
a donut shape. A hole 34 for containing the substrate 2 is provided
on the inner peripheral part of the second plate 29, and a
plurality of discharge ports 26 arrayed in a ring-shape are
provided on the outer peripheral part covering the recessed part
39a of the first plate 39. The second plate 29 is held by a stepped
part (protruding part) 41 provided on the inner peripheral part of
the processing chamber 1. A lower side of the sidewall 40 of the
upper container 46 is provided inwardly of the processing chamber 1
from an upper side, and a part where the lower side of the inner
sidewall 40b of the upper container 46 is inwardly protruded from
the upper side of the inner sidewall 40a, is defined as the
aforementioned stepped part 41. By holding the second plate 29 on
this stepped part 41, the gap between the stepped part 41 of the
processing chamber 1 and the second plate 29 is eliminated.
Note that out of the second plate 29, the inner peripheral part
side is called a plate inside part 29b, and the outer peripheral
part side is called a plate outside part 29a, with the discharge
port 26 as a border. Since the plate outside part 29a and the plate
inside part 29b are integrally formed, the aforementioned discharge
port 26 can not be continuously formed but discontinuously formed,
from necessity of supporting the plate inside part 29b by the plate
outside part 29a directly held on the stepped part 41.
Incidentally, in the aforementioned structure, as shown in FIG. 7,
when the susceptor 6 is lowered to the carry-in/carry-out position,
the first plate 39 is disposed below the substrate carrying port 10
so as not to cause obstruction for carrying in and carrying out the
substrate. The second plate 29 is held on the stepped part 41 in a
horizontal posture. After the substrate 2 is carried into the
processing chamber 1 and is placed on the thrust-up pin 8, the
susceptor 6 is lifted to the substrate processing position by a
lifting/lowering mechanism 9. The first plate 39 placed on the
susceptor 6 is lifted together with the susceptor 6, along with the
lift of the susceptor 6. In the intermediating point of lifting the
susceptor 6 to the substrate processing position, the substrate 2
is automatically placed on the first plate (flat plate part 39b)
placed on the susceptor 6, from the thrust-up pin 8.
As shown in FIG. 8, when the susceptor 6 is lifted to the substrate
processing position, the upper part of the opening of the recessed
part 39a of the first plate 39 is covered by the second plate 29
held at the substrate processing position, and the hollow part 27
is formed. This hollow part 27 becomes an exhaust passage having
the same function as the hollow part 27 of the first embodiment. In
this case, even if the gap is formed between the sidewall of the
plate 7 and the sidewall 40 of the processing chamber, the flow
passage leading to this gap from the upper part 1a of the
processing chamber is closed by the second plate 29 held on the
stepped part 41.
In this way, according to the second embodiment, the plate is made
separable, and the hollow part 27 is formed by covering the opening
upper part of the recessed part 39a of the first plate 39, with the
second plate 29. Therefore, in the same way as the case of an
integral type plate having the hollow part 27 of the first
embodiment, the gas supplied into the upper part 1a of the
processing chamber is distributed to the hollow part 27 from the
gas discharge port 26, then exhausted from the plate exhaust port
28 and exhausted outside the processing chamber 1 from the exhaust
port 5. Particularly, in the second embodiment, the flow passage
from the processing chamber 1a to the gap inevitably formed between
the sidewall of the plate 7 and the sidewall 40 of the processing
chamber is interrupted by the second plate 29 held on the stepped
part 41. Therefore, some gas supplied to the upper part 1a of the
processing chamber at the time of processing the substrate is
prevented from turning around the lower part 1b of the processing
chamber by passing through the aforementioned gap, without being
discharged into the hollow part 27.
In the aforementioned second embodiment, explanation has been given
to a case in which the first plate 39 is placed on the susceptor 6,
with an entire body of the upper surface of the susceptor 6 covered
by the first plate 39. However, as shown in FIGS. 10(a) and (b), in
the same way as the second plate 29, by forming the hole in which
the substrate 2 is disposed (received) in the center part of the
first plate 39, the first plate 39 may be placed on the susceptor 6
together with the second plate 29, while covering a part (outer
peripheral part) of the susceptor 6.
Incidentally, in the aforementioned embodiments of FIG. 7, FIG. 8
or FIG. 10, by closing the gap formed between the sidewall of the
plate 7 and the sidewall 40 of the processing chamber by the second
plate 29 placed on the stepped part 41, the turn-around of the gas
to the lower part 1b of the processing chamber from this gap is
prevented. In this case, it appears that the gap is formed between
the second plate 29 itself and the upper surface of the stepped
part 41. Namely, as shown in FIG. 9, when the opening upper part of
the recessed part 39a of the first plate 39 is covered by the
second plate 29 by lifting the susceptor 6, it appears that the
second plate 29 is lifted by the first plate 39, and a gap 31 is
formed between the stepped part 41 and the second plate 29.
Ideally, the first plate 39 should be come in contact with the
second plate 29 so as not to form the gap 31. However, formation of
the aforementioned gap 31 is inevitable, by an accuracy of the
lifting/lowering mechanism of the susceptor 6, and dimension
accuracy in manufacturing the first plate 39 and the second plate
29. When the conductance of this gap 31 becomes the conductance
that can not be neglected with respect to the discharge port 26, it
appears that the gas supplied to the silicon substrate 2 from the
supply ports 3 and 4 flows to the hollow part 27 from the discharge
port 26, being the gas flow passage, and also flows (turns-around)
to the lower part 1b of the processing chamber from the gap 31.
In this case, it is possible to make the conductance on the side of
the gap 31 smaller than the discharge port 26. However, an actual
dimension is estimated to be about 5 mm for the discharge port and
about 2 mm for the gap 31. In this case, as compared to the
discharge port 26, the gas of an amount that can not be neglected
from point of the gap 31 is exhausted.
In this point, the following knowledge is obtained. Namely, unless
the second plate 29 placed on the stepped part 41 is not lifted by
the first plate 39 when the first plate 39 is carried to the
substrate processing position, the gap 31 is not formed between the
stepped part 41 and the second plate 29. Such a situation further
makes the second plate 29 separable, and when the first plate 39 is
carried to the substrate processing position, one of the separated
plates of the second plate 29 is kept placed on the stepped part
41, and only the other separated plate of the second plate 29 is
lifted by the first plate 39. With this structure, the third
embodiment can be realized.
FIG. 11 shows the third embodiment as described above, wherein the
second plate 29 in the second embodiment is made separable, and by
not forming the gap 31 between the stepped part 41 and the second
plate 29, the aforementioned turn-around of the gas is prevented.
FIG. 11 is an explanatory view of an essential part of the
substrate processing apparatus, and (a) is a vertical sectional
view of an essential part at the time of carrying-in/carrying-out
the substrate, and (b) is a vertical sectional view of an essential
part at the time of processing the substrate. In addition, FIG. 14
is an explanatory view of the first plate 39, (a) is a perspective
view, (b) is a sectional view taken along the line A-A', and (c) is
a sectional view taken along the line B-B. Also, FIG. 15 is a
perspective view of separating the second plate 29.
As shown in FIG. 11, the first plate 39 is constructed by a type
covering an entire part of the upper surface of the susceptor 6. As
shown in FIG. 14(a), the first plate 39 has the recessed part 39a,
with the upper part opened outside, and has a circular flat plate
part 39b inside for covering the entire part of the upper surface
of the susceptor. The recessed part 38 is provided in the upper
surface center of this flat plate part 39b, so as to receive the
substrate 2 in the recessed part 38, and when the substrate 2 is
placed in the recessed part 38, the surface of the substrate 2 is
flush with the upper surface of the outer peripheral part of the
flat plate part 39b. A swelling part of the outer periphery of the
flat plate part 39 lifts the inside plate 29d as will be described
later, and in order not to lift an outside plate 29c, an upper
surface position of the part thus swelled may be set higher than
the position of the upper end part of the outer sidewall of the
recessed part 39a.
In addition, as shown in FIG. 14(b), the recessed parts 39a are
provided on both sides, and the plate exhaust port 28 is provided
on the exhaust port side opposite side of the gate valve side of
the recessed part 39a. Also, as shown in FIG. 14(c), the recessed
parts 39a with no plate exhaust port 28 are provided on both sides
of the first plate 39.
As shown in FIG. 11(a), the second plate 29 has an inside plate 29d
and an outside plate 29c, and they are made separable. The outside
plate 29c is placed on the stepped part 41. The inside plate 29d is
placed on this outside plate 29c. Specifically, as shown in FIG.
15, the second plate 29 has a ring-shaped inside plate 29d and a
ring-shaped outside plate 29c with larger outer diameter and
smaller inner diameter than the outer diameter of the inside plate
29d. An engagement part composed of the stepped part is formed on
the inner peripheral part of this outside plate 29c, and a
to-be-engaged part composed of the stepped part engaging with the
aforementioned engagement part is formed on the outer peripheral
part of the inside plate 29d. The inside plate part 29d is
concentrically placed on the outside plate 29c, so as to be
partially overlapped one another. As a partially overlapped
constitution, as shown in FIG. 11(a) and FIG. 15, it may be so
constituted that an overlapped portion is not made thicker by
engagement of the stepped parts, and when the inside plate 29d is
placed on the outside plate 29c, they are made to be a single
surface. When the susceptor 6 is located at a substrate
carry-in/carry-out position, the inside plate 29d is placed on the
outside plate 29c. Therefore, the gap becoming the discharge port
26 as will be described later is not formed between the inside
plate 29d and the outside plate 29c of the second plate.
As shown in FIG. 11(b), in a state of moving the susceptor 6 to the
substrate processing position, only the inside plate 29d comes in
contact with the first plate 39, and the outside plate 29c does not
come in contact with the first plate 39. By the aforementioned
contact of the inside plate 29d and the first plate 39, the inside
plate 29d is lifted by the first plate 39 and is separated from the
outside plate 29c, and the gap is formed between the inside plate
29d and the first plate 39. The discharge port 26 for discharging
the gas supplied into the upper part 1a of the processing chamber
is formed by this gap. Meanwhile, since the outside plate 29c does
not come in contact with the first plate 39, the gap between the
stepped part 41 and the outside plate 29c is kept closed, and the
gap is not formed.
In addition, as shown in FIG. 11(b), when the inside plate 29d
comes in contact with the first plate 39, the outer periphery of
the silicon substrate 2 is covered by the inside plate 29d. This is
because the inside plate 29d is made to have a film deposition
preventive function to the outer periphery of the silicon
substrate, which is required in some step of the substrate
processing steps.
As described above, according to the third embodiment, the gap is
not formed between the stepped part 41 and the second plate 29.
Therefore, from such a gap, the exhaust of the gas of the quantity
that can not be neglected can be efficiently prevented. Note that
as is clarified from a part surrounded by a dot-line of FIG. 11,
since the outside plate 29c does not come in contact with the first
plate 39, the gap 30 is formed between the outside plate 29c and
the first plate 39. Namely, it can be considered in such a way that
the gas supplied to the upper part 1a of the processing chamber and
discharged from the discharge port 26 into the hollow part 27 turns
around the lower part 1b of the processing chamber. However, in
this point, by enlarging an opening area of the plate exhaust port
28 provided in the first plate 39 and sufficiently enlarging the
conductance of this plate exhaust port 28, namely by making a
resistance of gas flow small, the gas discharged into the hollow
section 27 is prevented from turning around the lower part 1b of
the processing chamber from the gap 30.
Here, a comparison is made between the constitution of FIG. 11(b)
wherein the gap 30 is formed between the outside plate 29c and the
first plate 39, and the constitution of FIG. 9 wherein the gap 31
is formed between the outside plate 29c and the stepped part 41.
Then, it is found that in FIG. 9, the gas supplied to the silicon
substrate 2 from the supply ports 3 and 4 is discharged from both
of the gap 31 and the discharge port 26. Although the conductance
of the gap 31 is smaller than the conductance of the discharge port
26, the gas that can not be neglected is discharged from the gap
31, compared to the discharge port 26. Meanwhile, in FIG. 11(b),
the gas supplied to the silicon substrate 2 from the supply ports 3
and 4 flows to the hollow part 27 from the discharge port 26 which
is only one gas flow passage. In the hollow part 27, by largely
opening the plate exhaust port 28, the conductance of the plate
exhaust port 28 is made sufficiently larger than the conductance of
the gap 30. Whereby, gas leak from the gap 30 can be suppressed.
Here, even if it is so assumed that the gap 30 and the gap 31 have
the same dimension, from the difference in constitution as
described above, gas turn-around to the lower part 1b of the
processing chamber from the aforementioned gap can be more
prevented and the advantage of reducing the contact-gas area and
the flow passage volume is increased in the constitution of FIG.
11(b) than the constitution of FIG. 9.
In addition, in the third embodiment, it is also possible to make
the conductance of the gap 30 small, to suppress the gas flow from
the gap 30. For example, as shown in FIG. 12, a recessed place is
provided on the backside of the plate outside part 29a, and an
outside wall upper edge of the first plate 39 is engaged with this
recessed place so as not to be contacted with each other. According
to this third embodiment, a Labyrinth structure is formed by the
gap 30, and the conductance of the gap 30 becomes small, thus
making it possible to further suppress the gas flow from the gap
30.
As described above, according to the third embodiment, the gap is
not formed between the stepped part 41 and the second plate 29 when
the susceptor 6 is lifted, the opening upper part of the recessed
part 39a of the first plate 39 is covered by the second plate 29,
and the hollow part 27 is formed. Therefore, the turn-around of the
gas to the lower part 1b of the processing chamber by passing
through the gap does not occur. Also, at this time, the inside
plate 29d of the second plate 29 is elevated by the first plate 39,
and the gap for communicating the lower part 1a of the processing
chamber and the hollow part 27 is formed between the outside plate
29c and the inside plate 29d. Therefore, the discharge port 26 for
discharging the gas into the hollow part 27 of the plate 7 from the
upper part 1a of the processing chamber can be secured.
In addition, the third embodiment can be variously modified. For
example, in the third embodiment, the discharge port 26 formed by
the inside plate 29d and the outside plate 29c constituting the
second plate 29 has a function of adjusting the conductance, to
equalize the gas flow on the silicon substrate 2. However,
depending on the film deposition condition, the adsorption on the
silicon substrate 2 is mainly performed, and when the influence of
the gas flow is small, it is not necessary to adjust the
conductance. Therefore, the third embodiment may be modified to
have only the outside plate 29c of the first plate 39 and the
second plate 29.
In addition, in the third embodiment, explanation is given to a
case of covering a part of the substrate 2 by the second plate 29.
However, the substrate 2 may not be covered by the second plate 29.
When the substrate 2 is not covered by the second plate 29, a
division place between the first plate 39 and the second plate 29
forming the hollow part 27 can be variously modified. Such a
modified example is shown in FIG. 13.
In a plate structure of FIG. 13(a), a part corresponding to the
inside plate of the second plate covering a part of the recessed
part 39a is added to the first plate 39. In the second plate 29,
the part corresponding to the inside plate is removed, and it is
constituted only by a part corresponding to the outside plate
covering a remaining part of the recessed part 39a. In the plate
structure of FIG. 13(b), although the part corresponding to the
inside plate of the second plate is added to the first plate 39, a
rising part of the outside constituting the recessed part 39a is
removed. In the second plate 29, although the part corresponding to
the inside plate is removed, the part corresponding to the rising
part of the outside constituting the recessed part 39a is
added.
According to these modified examples, by changing the division
place between the first plate and the second plate, the part
corresponding to the inside plate covering the recessed part is
added to the first plate. Therefore, the second plate can be
constituted only by the part corresponding to the outside plate
always held by an unmovable stepped part 41, and thus the second
plate can be simplified.
In addition, in the aforementioned first to third embodiments,
explanation has been given to a case that any one of the supply
ports for supplying the gas into the processing chamber is a
flowing type in the diameter direction using the shower head.
However, the gas supplying method of the present invention is not
limited thereto, but can be applied to a one way flowing type.
Here, the one way flowing type is the type of supplying the gas
from the gas supply port provided on the sidewall of the substrate
to the surface of the substrate, allowing one way flow on the
substrate, and exhausting the gas from the exhaust port provided on
the opposite side of the gas supply port.
FIG. 16 is a vertical sectional view at the time of processing the
substrate, for explaining the single wafer type substrate
processing apparatus according to a fourth embodiment of the one
way flowing type. Basically, the fourth embodiment has the same
constitution as the third embodiment, and the same signs and
numerals are assigned to the same parts, and explanation therefore
is omitted. A different point is that the supply ports 3 and 4 are
provided so as to communicate with a space on the side of the
substrate 2 and above the plate 7, to thereby supply the gas to the
substrate 2.
As shown in the figure, the gas supply ports 3 and 4 are directly
connected to the substrate carrying port 10 side of the processing
chamber 1 of the upper container 46, without interposing the shower
plate, to thereby supply the gas into the processing chamber 1 from
above the plate 7. The gas flown to the upper part 1a of the
processing chamber above the plate 7 in the processing chamber 1
from the gas supply ports 3 and 4 collides against the second plate
29, then a course is changed, and some of the gas is discharged
into the hollow part 27 from the discharge port 26 on the upper
stream side to pass around the hollow part 27, which is then
exhausted to the exhaust port 5 from the plate exhaust port 28. The
residual gas performs one way flow toward the discharge port 26 on
the downstream side on the substrate 2 along the second plate 29,
and is discharged into the hollow part 27 from the discharge port
26, and is exhausted to the exhaust port 5 from the plate exhaust
port 28.
When the present invention is applied to the substrate processing
apparatus thus having the supply port of one way flow type, the gas
can be directly supplied into the processing chamber. Therefore,
the residual gas can be quickly exhausted, compared to a case of
supplying the gas through the shower plate. Therefore, the purge
efficiency can be further enhanced.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a vertical sectional view at the time of
carry-in/carry-out of a substrate for explaining a substrate
processing apparatus according to a first embodiment.
FIG. 2 is a vertical sectional view at the time of film deposition
for explaining the substrate processing apparatus according to the
first embodiment.
FIG. 3 is an explanatory view of a plate according to the first
embodiment, (a) is a plan view, (b) is a side view, (c) is a front
view, (d) is a sectional view taken along the line A-A', and (e) is
a sectional view taken along the line B-B.
FIG. 4 is a partially broken perspective view of the plate
according to the first embodiment.
FIG. 5 is an explanatory view showing a modified example of the
plate according to the first embodiment, (a) is a sectional view of
the plate of a type in which a discharge port does not have a
function of adjusting a conductance, (b) is a sectional view of the
plate of the type in which the plate covers an entire body of a
susceptor, and (c) is a sectional view of the plate in which a
plate exhaust port is provided in a range from an outside wall of a
hollow part to a bottom surface.
FIG. 6 is an explanatory view of a modified example of the plate
according to the first embodiment, and is a sectional view of the
susceptor integrally formed with the plate.
FIG. 7 is a vertical sectional view at the time of
carry-in/carry-out of the substrate for explaining the substrate
processing apparatus according to a second embodiment.
FIG. 8 is a vertical sectional view at the time of film deposition
for explaining the substrate processing apparatus according to the
second embodiment.
FIG. 9 is an expanded view of an essential part of FIG. 8.
FIG. 10 is an explanatory view showing the modified example of the
substrate processing apparatus according to the second embodiment,
(a) is a sectional view at the time of carry-in/carry-out of the
substrate, and (b) is a sectional view at the time of processing
the substrate.
FIG. 11 is an explanatory view of the substrate processing
apparatus according to a third embodiment, (a) is a sectional view
of an essential part at the time of carry-in/carry-out of the
substrate, and (b) is a sectional view of the essential part at the
time of processing the substrate.
FIG. 12 is a sectional view of the essential part at the time of
processing the substrate, showing the modified example of the
substrate processing apparatus according to the third
embodiment.
FIG. 13 is an explanatory view showing the modified example of the
substrate processing apparatus according to the third embodiment,
(a) is a sectional view of the essential part of an example in
which a second plate is composed of only an outside plate part and
(b) is a sectional view of the essential part of an example in
which the second plate is composed of only the outside plate part
and constitutes a part of a recessed part of a first plate.
FIG. 14 is an explanatory view of the first plate according to the
third embodiment, (a) is a perspective view, (b) is a sectional
view taken along the line A-A', and (c) is a sectional view taken
along the line B-B.
FIG. 15 is an explanatory view of the second plate according to the
third embodiment, showing a state that the outside plate and the
inside plate are separated from each other.
FIG. 16 is a vertical sectional view at the time of processing the
substrate, for explaining the substrate processing apparatus
showing another embodiment of a gas supplying method according to a
fourth embodiment.
FIG. 17 is an explanatory view showing a basic gas supplying method
common in an ALD, being a film deposition method, and a MOCVD, in
which a cycle-method is applied, (a) is a flowchart, and (b) is a
view of a gas supplying timing.
DESCRIPTION OF SIGNS AND NUMERALS
1 Processing chamber 2 Substrate 3.4 Supply port 5 Exhaust port 6
Susceptor 9 Lifting/lowering mechanism 10 Substrate carrying port
35 Exhaust duct 40 Processing chamber side wall
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